Read Online I know you got soul: machines with that certain something by Jeremy Clarkson - Free Book Online

debris too small to catalogue and tens of millions of man-made particles.
    This is beginning to make space travel in the vicinity of earth extremely hazardous. The Shuttle recently hit a paint chip, which doesn’t sound like the end of the world, but because of the speeds involved the tiny particle blew a hole halfway through one of its windows. More recently theFrench-made satellite
Cerise
was destroyed when it crashed into a piece of debris.
    Then there’s the bothersome business of all this rubbish coming back down to earth. It’s estimated that in 1999 nearly half a million pounds of junk re-entered the atmosphere. 84,000 lbs survived the heat and, because 25 per cent of the earth’s surface is land, we can deduce that 21,000 lbs didn’t fall harmlessly into the sea.
    In the eighties the Canadians had a bust-up with the Russians over large chunks of radioactive space waste that landed in the Northern Wilderness. And the Australian government charged NASA with littering after
Skylab
crash-landed in the outback.
    It’s all a far cry from the system of space communication dreamed up by the then-unknown science-fiction author Arthur C. Clarke. Back in 1945, in a paper called ‘Extra-Terrestrial Relays’, he suggested that three satellites positioned 22,000 miles from earth would mean the whole planet could be linked.
    It was a wonderful piece of speculation, especially since there was no way, back then, of reaching even five feet into space. Rocketry was limited to a handful of British geeks, who understoodit only in theory, and the Nazi V2s, which had a job reaching England, leave alone the heavens.
    So how Clarke thought his satellites could be taken to their carefully chosen mooring spots 22,000 miles away, God only knows.
    Actually, that’s not true. Today it isn’t only God that knows. Anyone with access to the internet can find out as well. The thing is, though, it’s a bit complicated. It really is rocket science.
    You see, in order to break free of the earth’s atmosphere you need to achieve a speed of 8 km per second. That’s 17,500 mph. And that’s pretty fast.
    At this speed your forward momentum exactly balances the downward gravitational acceleration so you achieve orbit. Fine, but it will be a low orbit, just a few miles up, and you will still be battling traces of friction from the atmosphere. In time, a few months maybe, your expensive satellite will start to slow down, and when that happens the people on earth had better stay indoors because it’s going to start raining steel…
    What you need is a huge rocket capable of getting you up to 17,500 mph and then, whenyou’re cruising round the world, another rocket to take you far, far away.
    22,000 miles, as Clarke predicted, is perfect because here the satellite has a huge view of earth – it can therefore beam its pictures or information to a wide area – and what’s more, for mathematical and scientific reasons I simply don’t understand, its speed can be perfectly matched to the rotation of the earth. Think. The dish that brings Jo Guest into your sitting room is pointing at a satellite that’s howling through space at thousands of miles per hour, but from your point of view on earth it’s always in the same place.
    This is handy. Imagine how annoying it would be if Jo were just about to remove her top when the satellite moved. You’d have to go outside with a ladder to wave your dish about until you found it again.
    Of course, pumping geo-stationary satellites into space today is a piece of cake. Even the French can do it. But back in the early days it wasn’t even remotely possible.
    The Russians were the first to get up there with
Sputnik
. It was little more than a radio beacon, screaming round the world beeping.
    The Americans were next. A huge mirror called
Echo
was sent up there, just getting out of the atmosphere where it reflected radio signals back to earth.
    The first proper satellite that could receive a signal, amplify it